The present invention relates to a dust collecting filter for filtering a fluid containing particles (hereinafter will be called "dust"), particularly to a radial flow type dust collecting filter provided with a cylindrical filtering wall for filtering the fluid flowing in the radial direction of the cylindrical filtering wall.
Conventionally, such filters as described above have been composed of a flat sheet-shaped porous filter member or a corrugated porous filter member which is formed into a cylindrical shape.
These filters are mainly used for filtering fluid of which dust content is small, namely the dust load is small, and for filtering fluid of which dust size is substantially uniform, namely the particle diameter range of the dust is narrow.
However, when the dust load is large and when the particle diameter of the dust is widely distributed, these filters cannot filter the fluid sufficiently.
Namely, when a conventional filter having large meshes is used, a considerable amount of dust passes the filter without being collected thereby so that high dust collecting efficiency cannot be obtained. When a conventional filter having small meshes is used, the filter is apt to be clogged by the dust so that the pressure loss of the fluid is increased.
Accordingly, one object of the present invention is to provide a radial flow type dust collecting filter wherein the filter member is effectively utilized to collect dust without being clogged thereby.
Another object of the present invention is to provide a radial flow type dust collecting filter which is suitable for filtering a fluid containing dust of which the load is large and of which the particle diameter is distributed over a wide range.